I have a 2000 Silverado 5.3, A/T with 130K miles. I am noticing a slight miss at idle when dropped into gear. If you raise the RPM slightly the miss goes away. I have access to a SNAP ON Motis but have had very little training, mainly what I have taught myself. The miss does not set a code. At idle with Motis you can see a 20 to 30 count misfire per 100 seconds cycle, half occurring on number 5 cylinder. The others are random between the other cylinders. I have replaced spark plugs and fuel filter. I have not tried plug wires yet. What else could be causing this?
This ad is not displayed to registered members. Register your free account today and become a member on Truckforums!
Chevrolet/GMC, Racing, Recreational Forum Moderator
Join Date: Apr 2009
Have you cleaned the throttle body? They are notorious for gumming up and causing a miss. I had one not too long ago that would shut off from such an irratic idle. A can of throttle body cleaner and it ran like new again. If not an injector may be the culprit.
__________________ 2003 Chevrolet Tahoe 4X4 5.3 2002 Chevrolet 2500HD 4X4 8.1 - BlackBear Tuned
there are some on this forum who have had problems with lifters....and a bad lifter will cause enough of a miss to "notice" but not set a code that being said I would try wires first and clean the throttle body
My 2000 gmc sierra 1500 just came from the shop because of a slight miss. I had the plugs replaced and it still has a slight miss. How do I clean the throttle body. The truck always starts fine the first time but subsequent starts take a crank or two. It also hesitates some times when I take off. Should I change the throttle position sensor. I am stumped but tired of paying 80 bucks for diagnosis that dont tell me ........ please help
I was only suggesting to check fuel pressure. I was stating my opinion a to what I thought might be the problem. Checking fuel pressure will rule out whether it is the fuel pressure reugaltor, or fuel filter, or fuel pump, or a wiring problem. Which then can suggest if it is a fuel problem, then narrow it down to a possible clogged injector. Shoulda elaborated more my fault.